[Viral pathogenic spectrum analysis of severe acute respiratory infection cases in Luohe City, Henan province from 2017 to 2019].

Objective: The purpose of this study was to investigate the characteristics of viral pathogen spectrum and the epidemiological characteristics of each viral pathogen in hospitalized cases associated with severe acute respiratory infection (SARI) in Luohe City, Henan Province from 2017 to 2019. Methods: Based the SARI Case Surveillance Platform, SARI cases were collected in Central Hospital of Luohe City, Henan Province from November 2017 to February 2019. In the end, 783 SARI cases were included, whose throat swabs were taken within 24 h of admission, as well as their demographic characteristics, onset time, clinical characteristics and other information recorded. At the same time, viral identification was performed, and the age and time distribution of each virus were analyzed. Results: The age of 783 SARI cases shown as M (P25, P75) was 3 (1, 5) years old, ranging from 1 month to 95 years old. Children under 5 years old were the majority (71.01%). The males (61.81%) were more than females (38.18%). Among the 783 SARI cases, a total of 9 kind of viruses were identified with 64.88% (508/783) of the throat swabs tested positive for at least one virus. The positive rate of influenza virus and human respiratory syncytial virus were both 20.18% (158 cases), which was the highest among all the detected respiratory virus. The co-infection rate was 15.84% (124/783), among which double infection was the most common, accounting for 85.48% (106/124) of the co-infected cases. And human respiratory syncytial virus, human rhinovirus and influenza virus were the most common pathogen in co-infection cases. Moreover, the viral positive rate was 68.71% in children aged 5 years and 63.27% in people aged 60-95 years. Influenza and human respiratory syncytial virus dominated in winter and spring, while human parainfluenza virus was the main infection in summer. Conclusion: Influenza virus and human respiratory syncytial virus were the main viruses in throat swabs of SARI cases from 2017 to 2019 in Luohe City, Henan Province. There were differences in the age and seasonal epidemiological characteristics of each virus.

MicroRNAs in gastric cancer: from bench to bedside.

Gastric carcinogenesis results from complex interactions between host and environmental and bacterial factors, and this leads to genetic and epigenetic deregulation of oncogenic and tumor-suppressive genes. MicroRNAs (miRNAs) are a class of small noncoding RNAs which regulate almost 30% of human genes post transcriptionally and they are crucial in the initiation and progression of various diseases; especially malignancies. Accumulated evidence documents changes in gene sequences and epigenetic modifications. These then lead to abnormal miRNA expression in gastric cancer (GC) and also to deregulated miRNAs which act as oncogenes or tumor suppressors by regulating related target genes and contributing to malignant phenotypes. This altered miRNA expression in body fluids could well provide a novel biomarker for GC patient diagnosis and prognosis. MiRNAs present a promising target for GC treatment, and more tempting, for eradication of gastric cancer stem cells. This latter sub-group of tumor cells is thought to initiate and maintain GC development. Herein, we review the aberrant expression of miRNA expression and the underlying mechanisms and consequential effects of miRNA de-regulation. This identifies the responsible gastric cancer target genes, and highlights potential clinical applications.

[Relationships between serum cystatin C, chemerin levels and subclinical atherosclerosis in type 2 diabetes mellitus patients].

Objective: To investigate the relationships between serum cystatin C (Cys C), chemerin levels and subclinical atherosclerosis in type 2 diabetes mellitus (T2DM) patients. Methods: A cross-sectional study was carried out between January 2016 and January 2018, and T2DM patients with carotid intima-media thickness (IMT) less than 1.1 mm were selected as subjects (100 males and 80 females, aged 40-60 years). The brachial-ankle pulse wave velocity (baPWV) ≥ 1 700 cm/s was set as the observation group (subclinical atherosclerosis) and baPWV<1 700 cm/s as the control group (non-subclinical atherosclerosis). Physical and blood examination were performed in both groups. Serum Cys C and chemerin levels were measured and their relationship with subclinical atherosclerosis was analyzed. Results: There was a statistically significant correlation between serum creatinine (r=0.167, P=0.011) and baPWV in the observation group, but not in the control group (r=0.105, P=0.070). Multiple linear regression analysis showed that age, duration of diabetes, serum creatinine, estimated glomerular filtration rate (eGFR), Cys C and chemerin were independently associated with baPWV, while high sensitive C reactive protein (hsCRP) and glycosylated hemoglobin (HbA1c) were not associated with baPWV. The elevation of serum Cys C (ß'=0.393, P=0.003) and chemokine (ß'=0.340, P=0.007) were correlative factors for atherosclerosis. Conclusion: The level of serum Cys C and chemerin is possibly related to the occurrence and development of subclinical atherosclerosis in T2DM patients.

Activated natural killer cells accelerate liver damage in patients with chronic hepatitis B virus infection.

Emerging evidence indicates that natural killer (NK) cells may contribute to liver injury in patients with hepatitis B virus (HBV) infection. Because HBV infection progresses through various disease phases, the cytolytic profiles of peripheral and intrahepatic NK cells in HBV-infected patients remain to be defined. In this study, we comprehensively characterized intrahepatic and peripheral NK cells in a cohort of HBV-infected individuals, and investigated their impact on liver pathogenesis during chronic HBV infection. The study population included 34 immune-clearance (IC) patients, 36 immune-tolerant (IT) carriers and 10 healthy subjects. We found that the activity of peripheral NK cells from IC patients was functionally elevated compared to IT carriers and controls, and NK cell activation was indicated by an increased expression of CD69, CD107a, interferon (IFN)-γ and tumour necrosis factor (TNF)-α. Further analysis showed that the increased activity of both peripheral and hepatic NK cells was correlated positively with liver injury, which was assessed by serum alanine aminotransferase levels (ALT) and the liver histological activity index (HAI). Interestingly, the frequency of peripheral NK cells was reduced in IC patients (especially those with higher HAI scores of 3-4), but there was a concomitant increase in hepatic NK cells. The functionally activated NK cells are enriched preferentially in the livers of IC patients and skew towards cytolytic activity that accelerates liver injury in chronic hepatitis B (CHB) patients.

Predictive factors for inadequate colon preparation before colonoscopy.

BACKGROUND: It could be helpful to ascertain which patients are at risk of poor bowel preparation prior to performing sedated colonoscopy. The aim of the present study was to identify the predictive factors for poor colon preparation prior to colonoscopy. METHODS: A prospective study was performed at Kaohsiung Chang Gung Memorial Hospital, Taiwan, from September 2011 to May 2013. Patient characteristics, food consumed within 2 days of colonoscopy, volume of polyethylene glycol (PEG) solution, interval between completing PEG and examination, number of bowel movements, and character of the last stool were evaluated. RESULTS: Seven hundred and three patients were enrolled (mean age 50.3 ± 11.6 years, 43 % female). In univariate analysis, character of the last stool (<0.001), body weight (p = 0.007), body mass index (p = 0.047), waist circumference (p = 0.008), buttock girth (p = 0.016), meal residue score (<0.001), and interval between end of PEG and colonoscopy (p = 0.01) were related to inadequate colon preparation. In multivariate analysis, waist circumference (p < 0.001), meal residue score (p < 0.001), and characteristics of last stool (p < 0.001) were variables that predicted poor colon preparation. CONCLUSIONS: Patients who have consumed a high residue diet and/or who report that their last stool is semisolid are likely to have poor bowel preparation, and consideration could be given to rescheduling the examination.

Risk factors influencing the outcome of peptic ulcer bleeding in end stage renal diseases after initial endoscopic haemostasis.

Background and Aims: Patients suffering from peptic ulcer (PU) bleeding who have end-stage renal disease (ESRD) may encounter more adverse outcomes. The primary objective is to investigate the risk factors that influence the outcomes of ESRD and chronic kidney disease (CKD) patients with PU bleeding after successful initial endoscopic haemostasis. Methods: A total of 540 patients with PU bleeding after initial endoscopic haemostasis in a tertiary hospital were investigated retrospectively. They were sorted into three groups after randomised age-matched adjustment: ESRD group (n = 90), CKD group (n = 90) and control group (n = 360). Main outcome measurements were rebleeding, requirement for blood transfusion and surgery, length of hospital stay and mortality. Results: The rebleeding rates were 43% for the ESRD group vs. 21% for the CKD group vs. 12% for the control group (overall p = < 0.001). Multivariate analysis showed the predictors of rebleeding were ESRD, time to endoscope, and non-high-dose proton-pump inhibitors (PPI) users. The risk factors for bleeding-related mortality were presence of moderate degree of CKD and ESRD group, time to endoscope, and Rockall score. All-cause mortality was related to presence of moderate degree of CKD and ESRD group, platelet count, time to endoscope, Rockall score and length of hospital stay. Conclusions: ESRD patients who suffered from PU bleeding were at risk of excessive rebleeding and mortality with frequent occurrence of delayed rebleeding. This study suggests that early endoscopy for initial haemostasis and high-dose intravenous PPI are associated with the reduction of rebleeding risk especially in patients with high Rockall scores.

The feasibility of QR-code prescription in Taiwan.

WHAT IS KNOWN AND OBJECTIVE: An ideal Health Care Service is a service system that focuses on patients. Patients in Taiwan have the freedom to fill their prescriptions at any pharmacies contracted with National Health Insurance. Each of these pharmacies uses its own computer system. So far, there are at least ten different systems on the market in Taiwan. To transmit the prescription information from the hospital to the pharmacy accurately and efficiently presents a great issue. METHODS: This study consisted of two-dimensional applications using a QR-code to capture Patient's identification and prescription information from the hospitals as well as using a webcam to read the QR-code and transfer all data to the pharmacy computer system. Two hospitals and 85 community pharmacies participated in the study. RESULTS AND DISCUSSION: During the trial, all participant pharmacies appraised highly of the accurate transmission of the prescription information. The contents in QR-code prescriptions from Taipei area were picked up efficiently and accurately in pharmacies at Taichung area (middle Taiwan) without software system limit and area limitation. The QR-code device received a patent (No. M376844, March 2010) from Intellectual Property Office Ministry of Economic Affair, China. WHAT IS NEW AND CONCLUSION: Our trial has proven that QR-code prescription can provide community pharmacists an efficient, accurate and inexpensive device to digitalize the prescription contents. Consequently, pharmacists can offer better quality of pharmacy service to patients.

Effects of miR-153 on angiogenesis in MCAO rats through Shh signaling pathway.

OBJECTIVE: Cerebrovascular disease is a disease which has the highest mortality in China. Angiogenesis in the ischemic region after cerebral infarction is closely related to its prognosis. Recent studies found that microRNAs (miRNAs) are involved in the regulation of neovascularization. MicroRNA-153 (MiR-153) has protective effects on the ischemic injury, but its relationship with the Sonic Hedgehog (Shh) signaling pathway is still unclear. This work aimed to investigate the role of miR-153 in angiogenesis of middle cerebral artery occlusion (MCAO) rats through the Shh signaling pathway. MATERIALS AND METHODS: The rat cerebral ischemic injury (MCAO) model was established by thread embolism and treated by Agomir-153 and 5-EI. MiR-153 expression was detected using Real Time-Polymerase Chain Reaction (RT-PCR). The neurological function was assessed. The infarct area of the brain and the capillary density were determined using 2,3,5-triphenyl tetrazolium chloride (TTC) method. The Shh signaling pathway and angiogenesis-related factors were tested by Western blot assay. RESULTS: Agomir-153 or Agomir-153 combined with 5-EI significantly increased miR-153 expression, reduced the infarct area, and promoted the generation of cerebral capillaries in the MCAO model. 5-EI partially blocked the protective effects of Agomir-153 and angiogenesis. The up-regulation of miR-153 markedly inhibited patched (PTC) expression and activated the Shh signaling pathway. CONCLUSIONS: The up-regulation of miR-153 rats activated the Shh signaling pathway to promote angiogenesis and improve prognosis through lipid-coated Patch (PTC) in MCAO. MiR-153 was considered to be a new therapeutic target for promoting angiogenesis after MCAO.

TGF-ß1 upregulates the expression of lncRNA UCA1 and its downstream HXK2 to promote the growth of hepatocellular carcinoma.

OBJECTIVE: TGF-ß1 plays pivotal roles in the development of various malignancies such as hepatocellular carcinoma, while the mechanism of the TGF-ß1 function in hepatocellular carcinoma remains unclear. Our study aimed to investigate the molecular mechanisms of the TGF-ß1 function in hepatocellular carcinoma. PATIENTS AND METHODS: Tumor tissues and adjacent healthy tissues were collected from hepatocellular carcinoma. Blood samples were collected from both hepatocellular carcinoma patients and healthy controls. Expression of TGF-ß1, long non-coding RNA (lncRNA) UCA1 and hexokinase 2 (HXK2) in those tissues was detected by qRT-PCR. All patients were followed up for 5 years, and prognostic values of serum HOTAIR for hepatocellular carcinoma were investigated by survival curve analysis. TGF-ß1, UCA1, and HXK2 overexpression hepatocellular carcinoma cell lines were established, and the effects on cell proliferation were detected by the CCK-8 assay. Interactions between TGF-ß1, UCA1, and HXK2 were explored by Western blot. Effects of TGF-ß1 on lactate production, glucose uptake, and ATP production were detected by lactate assay, glucose uptake assay, and ATP assay. RESULTS: TGF-ß1, UCA1, and HXK2 expression levels were upregulated in tumor tissues comparing with adjacent healthy tissues. Serum levels of TGF-ß1, UCA1, and HXK2 increased with the increases of primary tumor stage. Patients that have high serum levels of TGF-ß1, UCA1, and HXK2 showed lower overall survival rate compared with patients with low serum levels of TGF-ß1, UCA1, and HXK2. TGF-ß1, UCA1, and HXK2 overexpression promoted proliferation of hepatocellular carcinoma cell. TGF-ß1 is a positive upstream regulator of UCA1, which is a positive upstream regulator of HXK2. TGF-ß1 overexpression increased lactate production, glucose uptake and ATP production in hepatocellular carcinoma. CONCLUSIONS: TGF-ß1 may accelerate cancer cell energy metabolism to promote the growth of hepatocellular carcinoma by upregulating UCA1 and its downstream HXK2.

Oxidant stress inhibits the endogenous production of lipoxygenase metabolites in rat lungs and fish gills.

Hydroperoxides are potent initiators of lipid peroxidation in vivo. Acyl hydroperoxides may also regulate various aspects of lipid metabolism. In this study we investigated the regulation of the endogenous 12 lipoxygenase in trout gill and rat lung, a prominent acyl hydroperoxide catalyst in these tissues. Initial experiments revealed that the enzyme from trout gill was activated by hydroperoxides at low levels and inactivated by the same hydroperoxides at high levels. Homogenization of these tissues resulted in the production of a predominant metabolite class from released endogenous polyunsaturated fatty acids, the 12 lipoxygenase products. In rat lung, arachidonic acid was the major polyunsaturated fatty acid released and 12 (S) HETE was the major metabolite. In trout gill 20:4, 20:5 n3, and 22:6 n3 were released and the 12(S), 12, and 14 hydroxy derivatives the corresponding metabolites. Computer simulations of the sensitivity of these enzymes to hydroperoxides predicted that exogenous oxidant stress would reduce significantly the production of HETEs. Tertiary butyl hydroperoxide was added to tissue homogenates and resulted in elimination of greater than 95% of the lipoxygenase activity. These results suggest that the lipoxygenase enzyme in lung and gill tissue is a major potential source for acyl hydroperoxides in vivo, but is also very sensitive to oxidant stresses including the acyl hydroperoxides themselves. This enzyme could thus be an important focus for oxidant injury in lungs.

Vitamin E, diethylmaleate and bromotrichloromethane interactions in oxidative damage in vivo.

In vivo interactions of vitamin E with diethylmaleate (DEM) and bromotrichloromethane (CBrCl3) were examined in rats fed a diet either without vitamin E or supplemented with 30 IU dl-alpha-tocopheryl acetate/kg. Groups of rats within each dietary group were given two injections 30 min apart. One group received two injections of the mineral oil carrier. The other groups were injected with either DEM and mineral oil, mineral oil and CBrCl3, or DEM and CBrCl3. The rats were killed 10 min after the second injection. Measurements were made of hepatic GSH, thiobarbituric acid-reactive substances (TBARS) as a lipid peroxidation index, and 11 enzymes as potential markers of oxidant damage. Special focus was placed on reactive cysteine-containing aldehyde dehydrogenase (ALDH). Although dietary vitamin E protected ALDH, the enzyme was highly susceptible to oxidant damage. ALDH activity was correlated with GSH (r = 0.83, p less than 0.001) and there was an inverse relationship between the logarithmic values of ALDH activity and TBARS (r = 0.78, p less than 0.001). Similar results were observed for a number of other enzymes when GSH depletion preceded oxidant treatment. Two-way analysis of variance revealed significant effects of vitamin E and of injection treatments on hepatic GSH. There was a significant interaction between vitamin E and the injection treatments on the activities of five enzymes. The results suggested that vitamin E and GSH functioned together to protect sensitive enzymes against oxidant stress. The sensitive enzymes may be useful markers of hepatic damage in vivo.

Interaction of nitrogen dioxide with human plasma. Antioxidant depletion and oxidative damage.

Nitrogen dioxide (NO2.) is often present in inhaled air and may be generated in vivo from nitric oxide. Exposure of human blood plasma to NO2. caused rapid losses of ascorbic acid, uric acid and protein thiol groups, as well as lipid peroxidation and depletions of alpha-tocopherol, bilirubin and ubiquinol-10. No increase in protein carbonyls was detected. Supplementation of plasma with ascorbate decreased the rates of lipid peroxidation, alpha-tocopherol depletion and loss of uric acid. Uric acid supplementation decreased rates of lipid peroxidation but not the loss of alpha-tocopherol. We conclude that ascorbic acid, protein -SH groups, uric acid and alpha-tocopherol may be important agents protecting against NO2. in vivo. If these antioxidants are depleted, peroxidation of lipids occurs and might contribute to the toxicity of NO2..

In vitro hemolysis of rat erythrocytes by selenium compounds.

Rat erythrocytes were incubated in vitro with various selenium compounds at 37 degrees. Hemolysis occurred with some selenium compounds but not with corresponding sulfur analogues. Selenite induced more rapid loss of intracellular glutathione (GSH) than did selenocystine but was less hemolytic. Cystine caused neither loss of intracellular GSH nor hemolysis. Addition of GSH to the incubation medium enhanced hemolysis by selenite and selenium dioxide but inhibited hemolysis by selenocystine. Inclusion of glucose in the incubation medium also inhibited selenocystine-induced lysis of erythrocytes from both selenium-supplemented rats and selenium-deficient rats. The results suggest a relationship between the oxidation of intracellular GSH and the hemolysis by selenocystine, selenite and selenium dioxide.

DHEA inhibits cell growth and induces apoptosis in BV-2 cells and the effects are inversely associated with glucose concentration in the medium.

Dehydroepiandrosterone (DHEA), a major steroid secreted by the adrenal gland which decreases with age after adolescence, is available as a nutritional supplement. DHEA is known to have antiproliferative effects but the mechanism is unclear. In this study using BV-2 cells, a murine microglial cell line, we investigated the effect of DHEA on cell viability and the interaction between DHEA and glucose concentrations in the medium. We showed that DHEA inhibited cell viability and G6PD activity in a dose-dependent manner and that the effect of DHEA on cell viability was inversely associated with glucose concentrations in the medium, i.e. lowered glucose strongly enhanced the inhibition of cell viability by DHEA. DHEA inhibited cell growth by causing cell cycle arrest primarily in the G0--G1 phase, and the effect was more pronounced at zero glucose (no glucose added, G0) than high glucose (4.5 mg/ml of the medium, G4.5). Glucose deprivation also enhanced apoptosis induced by DHEA. At G4.5, DHEA did not induce formation of DNA ladder until it reached 200 microM. However, at G0, 100 microM DHEA was able to induce apoptosis, as evidenced by the formation of DNA ladder, elevation of histone-associated DNA fragmentation and increase in cells positively stained with annexin V-FITC and annexin V-FITC/propidium iodide. The interactions between DHEA and glucose support the contention that DHEA exerts its antiproliferative effects through alteration of glucose metabolism, possibly by inhibition of G6PD activity leading to decreased supply of ribose-5-phosphate for synthesis of DNA and RNA. Although DHEA is only antiproliferative at pharmacological levels, our results indicate that its antiproliferative effect can be enhanced by limiting the supply of glucose such as by energy restriction. In addition, the present study shows that glucose concentration is an important factor to consider when studying the antiproliferative and toxicological effects of DHEA.

Cigarette smoke oxidation of human plasma constituents.

In vitro exposure of fresh human plasma to cigarette smoke (CS) was used as a model for reactions that could be occurring in CS-exposed respiratory tract lining fluids (RTLFs) and lung parenchyma. The central focus of this model was to characterize the consumption of endogenous plasma antioxidants in relationship to the appearance of oxidized proteins and lipids as a consequence of exposure to CS, or to aldehydes present in CS. The amelioration of CS-induced protein and lipid oxidation in plasma by the addition of selective exogenous antioxidants was also assessed. We found that: (i) exposure of human plasma to gas phase CS causes both lipid peroxidation and protein oxidation, and endogenous ascorbic acid protects against lipid, but not protein, oxidation; (ii) whole CS causes protein oxidation, but does not induce lipid peroxidation; (iii) addition to plasma of aldehydes known to be present in CS causes protein damage, but does not induce either lipid peroxidation or oxidation of ascorbic acid; and (iv) exogenously added dihydrolipoic acid (DHLA) preserves ascorbic acid levels in plasma exposed to the gas phase of CS, and protects, to some extent, against lipid peroxidation; DHLA also protects against protein oxidation, whereas added glutathione (GSH) only protects against protein, but not lipid, oxidation.

Elevated lipid peroxidation and disturbed antioxidant enzyme activities in plasma and erythrocytes of patients with uterine cervicitis and myoma.

OBJECTIVES: We investigated whether oxidative stress is associated with human uterine cervicitis and uterine myoma. DESIGN AND METHODS: We measured lipid peroxidation and antioxidant enzymes in plasma and erythrocytes of cervicitis patients and myoma patients in comparison with matched controls. Thiobarbituric acid-reactive substances (TBARS), a measure of lipid peroxidation, were determined in plasma; glutathione peroxidase (GSHPx) and catalase in erythrocytes; and superoxide dismutase (SOD) in both plasma and erythrocytes. RESULTS: We showed that plasma TBARS were significantly higher (p < 0.05) in both cervicitis patients and myoma patients than in controls. Plasma TBARS were significantly (and negatively) correlated with plasma and erythrocyte T-SOD activities in cervicitis patients only. Plasma T-SOD activity was significantly lower in both groups of patients than in controls whereas erythrocyte T-SOD activity was only significantly lower in myoma patients. The lowered plasma T-SOD activity in the cervicitis patients was attributed to decreased Mn-SOD activity whereas the lowered plasma T-SOD activity in myoma patients was attributed to decreased activities of both Cu,Zn-SOD and Mn-SOD. Erythrocyte GSHPx activity was 14% higher (p < 0.05) in cervicitis patients and 11% lower (p > 0.05) in myoma patients than in controls; catalase activity was 10% higher (p > 0.05) in cervicitis patients and 13% lower (p > 0.05) in myoma patients than in controls. Neither erythrocyte GSHPx nor catalase activity was significantly correlated with plasma TBARS. CONCLUSIONS: The elevated lipid peroxidation and disturbed antioxidant enzyme activities demonstrate the potential of oxidative injury in patients with uterine cervicitis and myoma.

Total plasma malondialdehyde levels in 16 Taiwanese college students determined by various thiobarbituric acid tests and an improved high-performance liquid chromatography-based method.

OBJECTIVES: In determining the plasma malondialdehyde MDA levels in some Taiwanese college students, we found rather different results by using different thiobarbituric acid TBA tests, even by the high-performance liquid chromatography HPLC-based methods. Here, we re-evaluated four commonly used TBA tests and improved the HPLC-based test. DESIGN AND METHODS: We used the blood plasma of 16 college volunteers to determine plasma MDA by using four methods: a spectrophotometric measurement of thiobarbituric acid-reactive substances (TBARS) in the TCA-supernatant of plasma (Method A); a fluorescence measurement of plasma lipid peroxides (Method B); and two different HPLC-based measurements of MDA with either 532-nm measurement (Method C, HPLC/532 nm) or fluorescence measurement (Method D, HPLC/fluor.). RESULTS: The levels of MDA or TBA reactive substances obtained from the four methods differed substantially (0.39 +/- 0.15; 2.14 +/- 0.73; 0.75 +/- 0.22; and 0.38 +/- 0.15 microM for Methods A, B, C, and D, respectively). The results were positively correlated between Methods A and B (r = 0.740, p < 0.02) and between Methods C and D (r = 0.516, p < 0.05). However, results were negatively correlated between Methods B and D (r = -0.548, p < 0.05). Because most plasma MDA is bound to proteins, we modified the HPLC-based methods (C and D) by adding an alkaline hydrolysis step, and the plasma TBA-MDA adduct detected by HPLC/532 nm was referred to as total MDA. RESULTS show that alkaline hydrolysis was a critical step for measurement of total MDA in plasma because this treatment led to release of MDA from plasma proteins. We also adapted the potassium iodide (KI) treatment of plasma from Method D to reduce lipid hydroperoxides. Our modified method gave a total MDA level in the 16 volunteers of approximately 1.5 microM, which was equal to protein-bound MDA plus free MDA. This total MDA level was positively (p < 0.05) correlated with the level of TBA reactive substances obtained from Methods C (r = 0.63, p < 0.05) and D (r = 0.48, p < 0.07), but was not correlated with those from Methods A and B. The recovery (84 approximately 105%), precision (within-assay coefficient of variation: 2.4%, between-assay coefficient of variation: 4 approximately 8%) and sensitivity of the modified procedure were comparable to other HPLC-based methods. CONCLUSION: By using a validated modification of HPLC-based TBA method, the total plasma MDA in 16 Taiwanese college students was found to be 1.54 microM, which was relatively high compared to those obtained by other HPLC-based method, primarily due to the release of protein-bound MDA by alkaline hydrolysis. This level equaled the sum of protein-bound MDA and free MDA in plasma, confirming that this level represents total plasma MDA.

No detrimental effects in delaying initiation of gonadotropin administration after pituitary desensitization with gonadotropin-releasing hormone agonist.

OBJECTIVE: To determine if delaying initiation of exogenous gonadotropin administration after pituitary desensitization with gonadotropin-releasing hormone agonist (GnRH-a) is a realistic option to avoid scheduling clinical and laboratory work on weekends/holidays. DESIGN, PATIENTS: A review of 57 in vitro fertilization (IVF) cycles in which, after pituitary desensitization with GnRH-a, initiation of gonadotropin administration were delayed in an attempt to avoid off-hour work. Thirty-eight IVF cohort cycles served as control. SETTING: Tertiary medical center. RESULTS: There were no statistically significant differences in ovarian response, dose of gonadotropin required, oocytes and embryos obtained, pregnancy rates, and abortion rates between groups. Eighty-three percent of the delayed cycles had clinical and laboratory work that fell within weekdays. CONCLUSION: Delaying initiation of exogenous gonadotropin administration after pituitary desensitization had no detrimental effects on IVF outcomes. It may be used to avoid scheduling work on weekends/holidays.

Ascorbic acid inhibits lipid peroxidation but enhances DNA damage in rat liver nuclei incubated with iron ions.

In this report we studied DNA damage and lipid peroxidation in rat liver nuclei incubated with iron ions for up to 2 hrs in order to examine whether nuclear DNA damage was dependent on membrane lipid peroxidation. Lipid peroxidation was measured as thiobarbituric acid-reactive substances (TBARS) and DNA damage was measured as 8-OH-deoxyguanosine (8-OH-dG). We showed that Fe(II) induced nuclear lipid peroxidation dose-dependently but only the highest concentration (1.0 mM) used induced appreciable 8-OH-dG. Fe(III) up to 1 mM induced minimal lipid peroxidation and negligible amounts of 8-OH-dG. Ascorbic acid enhanced Fe(II)-induced lipid peroxidation at a ratio to Fe(II) of 1:1 but strongly inhibited peroxidation at ratios of 2.5:1 and 5:1. By contrast, ascorbate markedly enhanced DNA damage at all ratios tested and in a concentration-dependent manner. The nuclear DNA damage induced by 1 mM FeSO4/5 mM ascorbic acid was largely inhibited by iron chelators and by dimethylsulphoxide and mannitol, indicating the involvement of OH. Hydrogen peroxide and superoxide anions were also involved, as DNA damage was partially inhibited by catalase and, to a lesser extent, by superoxide dismutase. The chain-breaking antioxidants butylated hydroxytoluene and diphenylamine (an alkoxyl radical scavenger) did not inhibit DNA damage. Hence, this study demonstrated that ascorbic acid enhanced Fe(II)-induced DNA base modification which was not dependent on lipid peroxidation in rat liver nuclei.